Amniotic Fluid

Amniotic fluid is the clear, yellowish fluid that surrounds your baby in the amniotic sac. It is mainly made up of water, though from about week 10 of your pregnancy your baby will pass low levels of urine into it.

Throughout your pregnancy you carry about 800 mL of amniotic fluid in your womb, but from about week 38 that level decreases to approximately 600 mL by week 40. However, it is possible to have too much (polyhydramnios) or too little (oligohydramnios) amniotic fluid in your womb. These don’t tend to cause any complications, but your doctor will still monitor your pregnancy a little more closely than normal.

The important functions of the amniotic fluid include:

• helping to maintain a constant temperature within the amniotic sac
• protecting your baby against infection (it contains antimicrobial peptides)
• protecting your baby against bumps and injuries
• helping your baby to develop his breathing and swallowing skills and, of course, his lungs
• making movement inside of the amniotic sac easy so that your baby’s musculoskeletal system can develop